Collapsible Buttstock Assembly

ABSTRACT

Collapsible and extendable buttstock apparatus for use on a weapon having a buffer tube element. The apparatus is assembled onto the buffer tube and tightened in place using a compression clamp to hold the apparatus to the buffer tube. Upon release of the clamp the assembly can be slid along the buffer tube to a desired location and clamped in the preferred position.

BACKGROUND OF THE INVENTION Field of the Invention

This invention is a buttstock assembly for use in a semi-automatic rifle such as the “Colt” brand, “AR-15” brand (“Colt” and “AR-15” are trademarks of Colt Industries) as well as similar semi-automatic rifles or clones of the “Colt” “AR-15” semi-automatic rifle made by many companies throughout the world. The collapsible buttstock assembly presented here can also be used in rifles other than the AR-15 family of rifles having a similar lower receiver enabling attachment of the collapsible buttstock to the main body of the weapon. It is also contemplated that the collapsible buttstock assembly invention may be used on pistols as well as rifles.

Description of Known Art

Applicant believes that the material incorporated above is “non-essential” in accordance with 37 CFR 1.57, because it is referred to for purposes of indicating the background of the invention or illustrating the state of the art. However, if the Examiner believes that any of the above-incorporated material constitutes “essential material” within the meaning of 37 CFR 1.57(c)(1)-(3), applicants will amend the specification to expressly recite the essential material that is incorporated by reference as allowed by the applicable rules.

BRIEF SUMMARY OF THE INVENTION

The present invention provides, among other things, a collapsible and extendable buttstock for use with AR-15 style semi-automatic rifles. Another embodiment may be used on handguns as well.

An advantage of this collapsible and extendable buttstock is that the buttstock can be collapsed as necessary resulting in a shorter overall length of the weapon or the collapsible buttstock can be extended to allow better stabilization of the weapon when it is being used.

Another advantage of the invention is that the device is light, compact and simple to install and manufacture.

An object of this invention is to provide a collapsible buttstock that is easily attached to the lower receiver of an AR-15 style semi-automatic rifle.

It is also an object of the invention to provide a buttstock that is a direct fit into a lower receiver of an AR-15 style semi-automatic weapon without the need for any special tools, machining operations, or gunsmithing experience.

A feature of the invention is that the buttstock can be laterally adjusted to fit the user and provide a comfortable position of the host weapon at the shoulder of the user.

A further advantage is that this buttstock may enable better utilization of ammunition as the accuracy of the rifle is improved.

Another object of the invention is to provide a collapsible buttstock that can easily be installed without the need to hire a gunsmith to do the installation.

Aspects and applications of the invention presented here are described below in the drawings and detailed description of the invention. Unless specifically noted, it is intended that the words and phrases in the specification and the claims be given their plain, ordinary, and accustomed meaning to those of ordinary skill in the applicable arts. The inventors are fully aware that they can be their own lexicographers if desired. The inventors expressly elect, as their own lexicographers, to use only the plain and ordinary meaning of terms in the specification and claims unless they clearly state otherwise and then further, expressly set forth the “special” definition of that term and explain how it differs from the plain and ordinary meaning. Absent such clear statements of intent to apply a “special” definition, it is the inventors' intent and desire that the simple, plain and ordinary meaning to the terms be applied to the interpretation of the specification and claims.

The inventors are also aware of the normal precepts of English grammar. Thus, if a noun, term, or phrase is intended to be further characterized, specified, or narrowed in some way, then such noun, term, or phrase will expressly include additional adjectives, descriptive terms, or other modifiers in accordance with the normal precepts of English grammar. Absent the use of such adjectives, descriptive terms, or modifiers, it is the intent that such nouns, terms, or phrases be given their plain, and ordinary English meaning to those skilled in the applicable arts as set forth above.

Further, the inventors are fully informed of the standards and application of the special provisions of 35 U.S.C. § 112, ¶6. Thus, the use of the words “function,” “means” or “step” in the Detailed Description or Description of the Drawings or claims is not intended to somehow indicate a desire to invoke the special provisions of 35 U.S.C. § 112, ¶6, to define the invention. To the contrary, if the provisions of 35 U.S.C. § 112, ¶6 are sought to be invoked to define the inventions, the claims will specifically and expressly state the exact phrases “means for” or “step for, and will also recite the word “function” (i.e., will state “means for performing the function of [insert function]”), without also reciting in such phrases any structure, material or act in support of the function. Thus, even when the claims recite a “means for performing the function of . . . ” or “step for performing the function of . . . ,” if the claims also recite any structure, material or acts in support of that means or step, or that perform the recited function, then it is the clear intention of the inventors not to invoke the provisions of 35 U.S.C. § 112, ¶6. Moreover, even if the provisions of 35 U.S.C. § 112, ¶6 are invoked to define the claimed inventions, it is intended that the inventions not be limited only to the specific structure, material or acts that are described in the preferred embodiments, but in addition, include any and all structures, materials or acts that perform the claimed function as described in alternative embodiments or forms of the invention, or that are well known present or later-developed, equivalent structures, material or acts for performing the claimed function.

BRIEF DESCRIPTION OF THE DRAWING

A more complete understanding of the present invention may be derived by referring to the detailed description when considered in connection with the figures in which:

FIG. 1 is a projection of the right side of the collapsible/extendable buttstock assembly;

FIG. 2 is a projection of the left side of the collapsible/extendable buttstock assembly;

FIG. 3 is a side elevation view projection of the collapsible/extendable buttstock assembly;

FIG. 4 is a right side elevation view of the collapsible/extendable buttstock assembly sans a tightening wheel;

FIG. 5 is an end view of the collapsible/extendable buttstock assembly having an alternative tightening mechanism from which is shown in FIG. 1;

FIG. 6 is a right side elevation view of the collapsible/extendable buttstock assembly with the tightening wheel removed and showing two apertures for accommodating springs to spread the clamp for ease of installation and removal.

Elements depicted in the figure are illustrated for simplicity. They are presented to illustrate the invention to assist in an understanding thereof. The figures are not necessarily rendered according to any particular sequence, size, scale or embodiment.

DETAILED DESCRIPTION OF THE INVENTION

In the following description, and for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the various aspects of the invention. It will be understood, however, by those skilled in the relevant arts, that the present invention may be practiced without these specific details. In other instances, known structures and devices are shown or discussed more generally in order to avoid obscuring the invention. In many cases, a description of the operation is sufficient to enable one to implement the various forms of the invention, particularly when the operation is to be implemented in software. It should be noted that there are many different and alternative configurations, devices and technologies to which the disclosed inventions may be applied. The full scope of the invention is not limited to the examples that are described below.

Turning to FIGS. 1-6, the collapsible/extendable buttstock assembly is shown. Included in these figures are, among other elements, the adjustable buttstock assembly, generally 10; an attachment collar, also referred to as a “clamp” 12; left side 14 and right side 16 rails; and the stock end element 18, also referred to as the “butt.”

In FIGS. 1-3 a tightening wheel 20 is used to compress the body of the attachment collar 12. The tightening wheel shown includes a threaded shaft, not shown, that threads into a threaded aperture, also not shown, on the opposite side of the clamp 12. The aperture in right side leg of the “U-shaped” clamp would normally not be threaded. Only the aperture, which, in a preferred embodiment is a blind hole, on the left side leg of the “U-shaped” clamp will have internal threads. The clamp 12 is a generally “U-shaped” collar with a gap, slit, or open channel at the bottom of the “U.” This allows the clamp to be tightened on the host buffer tube (or extension tube), not shown, as the tightening wheel is tightened and the slit or open channel is compressed to clamp tightly to the buffer tube. The sides of the left 26 a and right 26 b channel walls will be securely clamped to and in contact with the rail on the underside of the standard buffer tube (not shown).

The tightening wheel 20 shown in FIGS. 1-3 is one of many possible designs. It has been found that a smaller diameter-tightening knob is sufficient in securing the buttstock extension to the buffer tube.

The rails, 14 and 16, are shown as being round in cross section. In other embodiments the rails can have a cross section other than round, such as, but not limited square, rectangular, obround, oval, or multi-sided.

In FIGS. 3 and 4 a partially internally threaded left aperture 28 a and a partially internally threaded right aperture 28 b represent through bores, having threaded sections, that extend from one side of the clamp 12, here the right side of the clamp 12, into apertures comprising blind holes on the left side of the clamp 12. These two bores will house compression springs, not shown, secured in the apertures by means of set screws screwed into the threaded portions of the bores or apertures 28 a and 28 b on the right side of the clamp. The blind holes on the left side of the clamp need not be threaded.

In FIG. 4 no tightening element is shown in order to clearly expose the apertures 28 a and 28 b. Many variations are possible.

FIG. 5 shows a lever-type tightening element 22. This lever-type tightening element is used in this embodiment instead of the tightening wheel or knob shown in the other figures. This lever includes a threaded projection that is screwed into the threaded aperture on the left side of the attachment collar or clamp 12 after a threaded portion of the lever element is passed through a non-threaded aperture on the right side of the clamp. There is a gap or space between the legs of the clamp and it is this gap that is diminished in width as the legs of the “U-shaped” clamp are forced together by tightening the clamp. To tighten the clamp the lever is rotated clockwise such that the threaded extension of the lever element is screwed into the threaded bore on the left side of the “U-shaped” clamp' to tighten the clamp on the host buffer tube and counter-clockwise to release compression on the buffer tube by the clamp.

The lever-type element 22 in FIG. 5, also called a “lifting lever” could be a cam operating locking lever. A cam surface between the inboard end of the lever and the side of the clamp 12 would provide a loose clamp when in one position and a tight clamping situation when the lever is rotated to the clamping position.

In the collapsible buttstock assembly presented here there are four main subassemblies. These are the attachment collar or clamp 12, the side rails 14 and 16, the stock end cap or “butt” 18, and the tightening mechanism such as the wheel 20 or the lever 22.

The rearward-facing end of the clamp 12 has a pair of apertures, 30 and 32, which are sized to receive the left 14 and the right side rail 16. The rails are press fit into the rearward facing apertures of the clamp. Alternatively the rails can be fastened into the clamp 12 by a screw connection, by gluing, or by welding.

The butt 18 of the device is spaced apart from the clamp by the left and right rails. The rails are inserted into receiving apertures 34 and 36 on the forward facing surface of the butt 18. In one embodiment the apertures 34 and 36 are blind holes and the rails are press fit into the blind holes. In another embodiment the rails are glued into the blind holes. In still a further embodiment, shown in FIG. 4, the apertures 34 and 36 are through bores and the ends of the rails are machined with threaded apertures to accept a threaded retainer to retain the butt to the ends of the rails.

One embodiment of the stock end element, the butt 18 structure, is shown in the figures. This embodiment is generally elongated and taller than it is wide. It is shaped to emulate the end of the buttstock of a rifle and provide a comfortable interface between a shooters shoulder and the butt end of the host rifle. This embodiment has a void interior space enclosed by the perimeter of the butt. In an alternative embodiment the top section of the butt, that is from just above the location where the rails are attached to the stock end element to the top of the stock end element 18. Closing off of this section of the butt can be done by a thin wall of material integral with the back side of the butt or by having that portion of the but being a filler that is as thick as the perimeter of the butt 18.

In another embodiment of the butt or stock end element 18 the entire open area of the butt as shown in various figures is totally covered over so there is no void space inside the perimeter of the butt. The cover or filler of the void space of the butt can be a relatively thin cover, full depth filler, or any depth of filler as designated. Same for situations where only the top portion of the butt is closed off. Weight is a concern, so it is advantageous to minimize the depth of the filler as long as it is not structurally compromised.

It is also an element of a preferred embodiment that the upper inboard or forward facing portion of the butt not be filled to the entire depth of the thickness of the perimeter of the butt. It is preferred that some depth in the filled section is left void to enable the assembly 10 to slide as far forward as possible and have the end of the buffer tube projecting into the cavity on the inboard side of the butt.

It should be pointed out that the buttstock assembly could be slid along the buffer tube that is surrounded by the clamp to a lateral position comfortable to a user. It need not be slid all the way to the end of the buffer tube but could have the clamp positioned partway along the buffer tube.

When the outboard surface of the butt 18, the surface that will be in contact with a user's shoulder, is entirely filled in, or even only partly filled in, the exposed outboard surface can be smooth or feature a textured surface. The textured surface may assist in stabilizing the host rifle when it is in use and the butt is in contact with the shoulder of the user.

The collapsible aspect of the invention is accomplished by sliding the entire assembly longitudinally along the buffer tube of the host rifle. In a collapsed position the assembly 10 may be slid forward on the buffer tube. The clamp 12 can be tightened using the wheel 20 or a lever-type tightening element (FIG. 5) to restrain the assembly in the collapsed position. In use the assembly 10 will be slid back toward the outboard end of the buffer tube and the wheel or lever will again tighten the attachment collar or clamp onto the host buffer tube as will be appreciated by a person having a familiarity with rifles or handguns having a buffer tube.

It is preferred to cast, machine, or fabricated the collapsible buttstock assembly from aluminum with steel or other hard metal elements in wear zones if deemed necessary. The inventor also contemplates making the assembly from non-aluminum metals, such as, but not limited to steel, or from non-metallic materials such as high performance plastics or other polymer based materials. Metal inserts may be necessary at wear points when non-steel materials are used.

The layout and structure of the collapsible buttstock assembly allows it to be fitted directly on the buffer tube assembly of an AR-15. No machining of the lower receiver assembly or of a standard buffer tube assembly is required. No special gunsmithing skills are needed.

In summary the invention disclosed herein is a buttstock assembly for use on a weapon that has a buffer tube. In the most basic embodiment the buttstock assembly includes a clamp; a left side rail and a right side rail, each rail connected at a first end of each rail to the clamp; and a butt element of the butt stock assembly. The butt element is connected to a second end of each of the left side rail and a right side rail such that the clamp and the butt element are connected together by the side rails.

The clamp is a generally “U-shaped” element having an adjustable width space or gap between the legs of the “U-shaped” clamp; and there is a tightening element carried on the clamp. This tightening element is provided for adjusting the width of the space between the legs of the “U-shaped” clamp. Thus narrowing the width of the space or gap between the legs of the clamp secures the buttstock assembly to the buffer tube of the weapon. To facilitate functioning of the clamp the legs of the “U-shaped” clamp have an aligned aperture extending from a right side aperture to a left side aperture with a portion of the left side aperture threaded and the right side aperture is a smooth bore. In one embodiment the tightening element has a wheel or knob element with a threaded extension projecting from the wheel or knob. This threaded portion of the threaded extension is positioned through the smooth bore of the right side aperture, across the space or gap between the legs of the “U-shaped” clamp, and into the threaded left side aperture of the clamp.

Another embodiment of the tightening device is a lifting lever with a threaded extension projecting from the lifting lever. In this embodiment the threaded portion of the threaded extension is positioned through the smooth bore of the right side aperture, across the space between the legs of the “U-shaped” clamp and into the threaded left side aperture of the clamp.

In order to spread the legs of the clamp to allow the collapsible buttstock assembly to move along the buffer tube the clamp has a lower portion below the location of where the rails are connected to the clamp. This lower portion defines a gap between a left and a right side of the clamp. There is a left aperture and right aperture in the lower portion of the clamp.

A pair of springs, one of each of the pair of springs carried in one of each of the apertures in the lower portion of the clamp will open up the gap between the legs of the clamp when the tightening device is moved to relieve tension. The springs are restrained through the provision of the left aperture and the right aperture having internal threaded portions with a pair of setscrews, one setscrew screwed into each threaded portion of the apertures. Each setscrew retaining one spring in the left aperture and one spring in the right aperture, whereby the springs will urge the legs of the “U-shaped” clamp outwardly.

It should be pointed out that the clamp defines a cavity having a modified generally cylindrical interior shape, the cavity open at both ends of the cylinder. This cavity is sized to accommodate the buffer tube of a weapon. The cavity also incorporates an extension of the cavity, the extension depending from the generally cylindrical interior shape. This extension defined by a left side channel wall and a right side channel wall, whereby the left side channel wall and a right side channel wall will contact the buffer tube when the buttstock assembly is positioned on the buffer tube.

The butt element of the buttstock assembly, in one embodiment has a perimeter defining a void area inside the perimeter of the buttstock assembly. In another embodiment the butt element of the buttstock assembly has a perimeter defining void area being less than the entire interior of the buttstock assembly as defined by the buttstock perimeter.

A further embodiment is that the butt element of the buttstock assembly is a panel with an outboard surface and an inboard surface. This panel has a width less than the height of the butt element. In a preferred embodiment the outboard surface of the butt element has a friction-inducing surface formed on the outboard surface of the butt element.

In further summary the invention is a buttstock assembly for use on a weapon, the weapon including a buffer tube. The buttstock assembly has a clamp being a generally “U-shaped” element having an adjustable width space or gap between the legs of the “U-shaped” clamp; and a tightening element carried on the clamp. This tightening element is capable of adjusting the width of the space between the legs of the “U-shaped” clamp. The legs of the “U-shaped” clamp have an aligned aperture extending from a right side aperture to a left side aperture with a portion of the left side aperture threaded and the right side aperture is a smooth bore. The clamp also has a tightening element including a threaded extension with the threaded portion of the threaded extension positioned through the smooth bore of the right side aperture, across the space between the legs of the “U-shaped” clamp and into the threaded left side aperture of the clamp. The assembly includes a left side rail and a right side rail, each rail connected at a first end of each rail to the clamp. It also includes a butt element of the butt stock assembly connected to a second end of each of the left side rail and a right side rail, whereby the clamp and the butt element are connected together by the side rails.

In one embodiment of the device the butt element of the buttstock assembly is a panel with an outboard surface and an inboard surface as discussed above. This panel has a width less than its height. In this version the outboard surface of the butt element has a friction-inducing surface formed on the outboard surface of the butt element.

While the invention is described herein in terms of preferred embodiments and generally associated methods, the inventor contemplates that alterations and permutations of the preferred embodiments and methods will become apparent to those skilled in the art upon a reading of the specification and a study of the drawings. 

1) A buttstock assembly for use on a weapon, the weapon including a buffer tube, the buttstock assembly comprising: a clamp; a left side rail and a right side rail, each rail connected at a first end of each rail to the clamp; a butt element of the butt stock assembly, the butt element connected to a second end of each of the left side rail and a right side rail, whereby the clamp and the butt element are connected together by the side rails. 2) The invention in accordance with claim 1 further comprising: the clamp being a generally “U-shaped” element having adjustable width space between the legs of the “U-shaped” clamp; and a tightening element carried on the clamp, the tightening element capable of adjusting the width of the space between the legs of the “U-shaped” clamp, whereby narrowing the width of the space between the legs secures the buttstock assembly to the buffer tube of the weapon. 3) The invention in accordance with claim 2 further comprising: the legs of the “U-shaped” clamp have an aligned aperture extending from a right side aperture to a left side aperture with a portion of the left side aperture threaded and the right side aperture is a smooth bore; and the tightening element comprises a wheel portion and threaded extension projecting from the wheel, the threaded portion of the threaded extension positioned through the smooth bore of the right side aperture, across the space between the legs of the “U-shaped” clamp and into the threaded left side aperture of the clamp. 4) The invention in accordance with claim 2 further comprising: the legs of the “U-shaped” clamp have an aligned aperture extending from a right side aperture to a left side aperture with a portion of the left side aperture threaded and the right side aperture is a smooth bore; and the tightening element comprises a lifting lever and threaded extension projecting from the lifting lever, the threaded portion of the threaded extension positioned through the smooth bore of the right side aperture, across the space between the legs of the “U-shaped” clamp and into the threaded left side aperture of the clamp. 5) The invention in accordance with claim 1, the clamp further comprising: a lower portion below the location of where the rails are connected to the clamp, the lower portion defining a gap between a left and a right side of the clamp; a left aperture and right aperture in the lower portion of the clamp. 6) The invention in accordance with claim 5 further comprising a pair of springs, one of each of the pair of springs carried in one of each of the apertures in the lower portion of the clamp. 7) The invention in accordance with claim 6 further comprising: the left aperture and the right aperture have internal threaded portions; and a pair of set screws, one set screw screwed into each threaded portion of the apertures, each set screw retaining one spring in the left aperture and one spring in the right aperture, whereby the springs will urge the legs of the “U-shaped” clamp apart. 8) The invention in accordance with claim 1 wherein the clamp further comprises: the clamp defining a cavity having a modified generally cylindrical interior shape, the cavity open at both ends of the cylinder, the cavity sized to accommodate the buffer tube of a weapon; an extension of the cavity, the extension depending from the generally cylindrical interior shape, the extension defined by a left side channel wall and a right side channel wall, whereby the left side channel wall and a right side channel wall will contact the buffer tube when the buttstock assembly is positioned on the buffer tube. 9) The invention in accordance with claim 1 further comprising: the butt element of the buttstock assembly having a perimeter defining a void area inside the perimeter of the buttstock assembly. 10) The invention in accordance with claim 1 further comprising: the butt element of the buttstock assembly having a perimeter defining a void area inside the perimeter of the buttstock assembly, the void area being less than the entire interior of the buttstock assembly as defined by the buttstock perimeter. 11) The invention in accordance with claim 1 further comprising the butt element of the buttstock assembly being a panel with an outboard surface and an inboard surface, the panel having a width less than the height of the butt element. 12) The invention in accordance with claim 1 further comprising the outboard surface of the butt element having a friction-inducing surface formed on the outboard surface of the butt element. 13) A buttstock assembly for use on a weapon, the weapon including a buffer tube, the buttstock assembly comprising: a clamp being a generally “U-shaped” element having an adjustable width space between the legs of the “U-shaped” clamp; and a tightening element carried on the clamp, the tightening element capable of adjusting the width of the space between the legs of the “U-shaped” clamp; the legs of the “U-shaped” clamp have an aligned aperture extending from a right side aperture to a left side aperture with a portion of the left side aperture threaded and the right side aperture is a smooth bore; and the tightening element including a threaded extension, the threaded portion of the threaded extension positioned through the smooth bore of the right side aperture, across the space between the legs of the “U-shaped” clamp and into the threaded left side aperture of the clamp; a left side rail and a right side rail, each rail connected at a first end of each rail to the clamp; a butt element of the butt stock assembly, the butt element connected to a second end of each of the left side rail and a right side rail, whereby the clamp and the butt element are connected together by the side rails. 14) The invention in accordance with claim 13 further comprising: the butt element of the buttstock assembly being a panel with an outboard surface and an inboard surface, the panel having a width less than the height of the butt element; and the outboard surface of the butt element having a friction inducing surface formed on the outboard surface of the butt element. 15) A collapsible buttstock assembly for use on a weapon, the weapon including a buffer tube, the collapsible buttstock assembly configured to allow a sliding relationship between the collapsible buttstock assembly and the buffer tube, the collapsible buttstock assembly comprising: a clamp that encircles the buffer tube when the collapsible buttstock assembly is positioned on the buffer tube; a left side rail and a right side rail, each rail connected at a first end of each rail to the clamp; a butt element of the butt stock assembly, the butt element connected to a second end of each of the left side rail and a right side rail, whereby the clamp and the butt element are connected together by the side rails. 